[x]You'll explore the idea that they could perhaps defect -they don't have Burner Worms, one of them seems to want to defect, and none of them seem all that devoted to 'the cause'.
-[x] Tell them that a merchant has been buying 'holy bread' from the priests of Neustadt des Glaubens, and, thinking it was only candied bread, selling them to Dominator lands. And also feeding animals with the bread. People and animals have thus been getting burned alive, and the newborn Brandstifters extinguished wherever they can be found.
-[x] Ask them if they know any priests who would do this. Who would either hate Dominated so much they would profane holy bread to burn Dominated peasants, or be venal enough to sell holy bread to a merchant and not care where the merchant would go on to sell the bread. The merchant claimed that "the folks back in Sables De La Haines love it" and have presumably been devouring them in great quantities. And yet there's supposedly not enough for the citizens of Neustadt?
[X]You'll accept their surrender more properly, have the Workers tie them up, and come back to this topic after... whatever happens with Neustadt tonight.